Process of manufacturing insulators



P. J. H. BERNARD.

PROCESS or MANUFACTURING msumons.

APPLICATION mm PAN/29,1919.

Patented May 18, 1920.

% Ill/HUN umwmumm m I1)WWI!IHIMUMLUJJMEEZ PIERRE JOSE-PH HENRI BERNARD,F -MON'1REAL, QUEBEC, CANADA.

PROCESS OF 'MANUFACTURING INSULATGRS.

Application filed May 29. 1919.

To all whom it may concern Be it known that I, Pruner. J OSEPH HENRIBERNARD, a subject of the King of Great Britain, residing at Montreal,Province of Quebec, Canada, have invented certain new and usefulImprovements in Processes of Manufacturing Insulators; and I do herebydeclare that the following is a full, clear, and exact description ofthe invention, such as will enable others skilled in the art to which itappertains to make and use the same.

The present invention relates to the man nor of making insulators andmore particularly to a process for making insulators from commercializedsheets of mica. The purpose of the invention is to provide a micainsulator which, when formed, will be a solidified mass obtaining ahigher degree of insulation value.

With the above and other objects in view which will hereinafter appearas the description continues, the invention consists of the novelfeatures of construction, combination and formation of parts as will behereinafter more fully described and particularly point- I ed out in theappended claim.

In the accompanying drawings Figure 1 is a plan view of one of the micadisks;

Fig. 2 is a sectional view of the disks as placed upon a metallic barshowing the first operation of the process;

Fig. 3 is a similar View showing the mica disks after being subjected toheat and pressure;

Fig. 4 is a similar View with a part thereof in elevation showing theinsulator when formed in a solid mass;

Fig. 5 shows the manner in which the spiral grooves may be formed withinthe insulator; and,

Fig. 6 is a side elevation of the insulator when completed.

Referring now more particularly to the accompanying drawings whereinlike and corresponding parts are designated by similar referencecharacters throughout the several views,

In the manufacture of mica plates suitable forinsulatingmaterial,theplates are formed by taking a plurality of superposed layers of micascales. which are covered with a finely powdered gum or rosin and thensubjecting the mass to heat and pressure to form the mica plates. Thesemica plates Specification of Letters Patent.

Patented May 18, 1920.

Serial No. 300,653.

are commercially available at the present time but are not suitable forinsulators which require a very high degree of insulation value, due tothe fact that when the coating of gum and rosin upon the plates isheated to a very high degree, the coating will expand causing the meansof mounting the insulator to give and at most times break.

In the forming the insulator embodying the present invention, theseplates of commercialized mica are cut to form the disks as shown inFig. 1. These disks are then placed upon a metallic bar 10 between astationary flange and the adjustable flange 30. A nut having screwthreads meshing with the metallic barlO is provided for adjusting theflange 30. This bar 10 having a plurality of mica sheets thereupon, asbetter illustrated in Fig. 2, is subjected to a red heat and at the sametime the nut 40 is tightened so to obtain a high degree of pressure uponthe mica plates. By subjecting these mica plates to heating pres surethe gases arising from the coatings from the plates which consists ofgum and rosin, will escape and leave a residue of carbon which would notexpand. Ofttimes, in subjecting these mica plates to the first operationof heat, and also subjecting the same to pressure, the bar 10 breaks asthe coating upon the mica plates has a tendency to expand when beingheated, and the mica sheets are subjected several times to this heatingand applying pressure until they eventually form in a position upon thebar 10 as shown in Fig. 8, and finally the mica is formed in a compactand solid block as shown in Fig. 4, as the gum and rosin con tained oneach sheet of mica have been taken out. This solid block of mica asindicated by the numeral 50, in Fig. 5, is placed upon a rod where thespiral grooves are formed in the periphery thereof as shown,subsequently forming the finished article as shown in Fig. 6, which is avery sufiicient insulator having a very high degree of insulation valueand very strong and durable. The grooves formed within the periphery ofthis block of mica, are for the reception of a high resistance carbon orcoil.

Having thus fully described my invention, what I claim as new and desireto secure by Letters Patent is 2-- A process of making insulatorsconsisting in arranging a plurality of mica sheets each containing acoating consisting of'gum on a lathe, to provide a continuous spiral androsin upon a supporting bar, repeatedly groove for the reception of theresistance subjecting the mica sheets to heat and preselement. 7 V Vsure whereby the gases from the coating of In Witness whereof I havehereunto set 5 gum and rosin will escape and the mica my hand.

sheets reduced to a solid consistency and a 7 then turning the resultantsolidified mass PIERRE JOSEPH HENRI BERNARD.

